spi: add support for device table matching

With this patch spi drivers can use standard spi_driver.id_table and
MODULE_DEVICE_TABLE() mechanisms to bind against the devices.  Just like
we do with I2C drivers.

This is useful when a single driver supports several variants of devices
but it is not possible to detect them in run-time (like non-JEDEC chips
probing in drivers/mtd/devices/m25p80.c), and when platform_data usage is
overkill.

This patch also makes life a lot easier on OpenFirmware platforms, since
with OF we extensively use proper device IDs in modaliases.

Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com>
Cc: David Brownell <dbrownell@users.sourceforge.net>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Grant Likely <grant.likely@secretlab.ca>
Cc: Jean Delvare <khali@linux-fr.org>
Cc: Ben Dooks <ben-linux@fluff.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/scripts/mod/file2alias.c b/scripts/mod/file2alias.c
index 40e0045..9d446e3 100644
--- a/scripts/mod/file2alias.c
+++ b/scripts/mod/file2alias.c
@@ -657,6 +657,15 @@
 	return 1;
 }
 
+/* Looks like: S */
+static int do_spi_entry(const char *filename, struct spi_device_id *id,
+			char *alias)
+{
+	sprintf(alias, "%s", id->name);
+
+	return 1;
+}
+
 static const struct dmifield {
 	const char *prefix;
 	int field;
@@ -853,6 +862,10 @@
 		do_table(symval, sym->st_size,
 			 sizeof(struct i2c_device_id), "i2c",
 			 do_i2c_entry, mod);
+	else if (sym_is(symname, "__mod_spi_device_table"))
+		do_table(symval, sym->st_size,
+			 sizeof(struct spi_device_id), "spi",
+			 do_spi_entry, mod);
 	else if (sym_is(symname, "__mod_dmi_device_table"))
 		do_table(symval, sym->st_size,
 			 sizeof(struct dmi_system_id), "dmi",